In recent years, a fuel cell favorable in view of environments focuses the spotlight of attention as a power source for a moving object such as an automobile, and development work has been undertaken to provide a fuel cell system adapted to achieve control for electric power generation of a fuel cell.
Especially, as one of those fuel cell systems which attract public attention to be influential as a fuel cell of the moving object, it has been proposed to provide a polymer electrolyte fuel cell (PEFC) with a polymer electrolyte formed with a proton exchange membrane (PEM).
Further, another fuel cell system has been proposed in which, in order to obtain hydrogen as fuel of the fuel cell, a fuel reformer system is installed to separate hydrogen from compound involving hydrogen.
Among these fuel cell systems, particularly, since organic compound, including carbon and hydrogen which form objects to be reformed, has an energy density per volume and an energy density per weight higher than those of hydrogen, considerable studying works and development works have been undertaken with respect to reforming through the use of such organic compound. Because, as organic compound, hydrocarbon fuel includes alkane such as methane, alcohol and ether series or gasoline which take the form of liquid under a normal temperature and normal pressure or under a pressurized condition to provide an ease of handling while a technology of using hydrocarbon as fuel has been established, hydrocarbon fuel is considered to be top-rated as raw material for fuel reforming.
Furthermore, in the fuel cell systems for the moving objects, it has been proposed to provide a fuel cell system in which an electric storage unit such as a secondary battery and a capacitor is installed. In a case that the fuel cell system is installed on the automobile, regenerative power, resulting from a halt of the moving object when in braked condition, is recovered and stored in the electric storage unit to allow the regenerative power to be utilized again as an energy for acceleration, thereby achieving improvement over a fuel consumption efficiency. Also, due to an ability of the electric storage unit to electronically control an overall fuel cell system, the electric storage unit is used as a power supply during a system stoppage with no electric power being generated by the fuel cell, enabling start-up operation of the fuel cell system to be commenced. There are many probabilities in which a secondary battery with a large energy density is incorporated in the electric storage unit.
Japanese Patent Application Laid-Open Publication No. 2002-117876 discloses a fuel cell system with a coolant flow passage provided, for the purpose of warming up a fuel cell, with a heating mechanism to heat coolant during a cold stage of the fuel cell.
Japanese Patent Application Laid-Open Publication No. 2002-198081 discloses a fuel cell system wherein when commencing operation of a fuel-cell fuel gas generating device equipped with an auto-thermal reformer, during warm-up of a reforming reactor including such a reformer and a CO remover unit, the flow rates of fuel and air to be supplied to the reformer during warm-up thereof are increased to promote warm-up of the CO remover unit.
Japanese Patent Application Laid-Open Publication No. 2002-83606 discloses a fuel cell co-generation system wherein a fuel cell is operated on a predetermined time pattern and corrects the predetermined time pattern depending on an electric power pattern that is actually consumed.
Japanese Patent Application Laid-Open Publication No. 2002-50378 discloses a fuel cell system wherein if a secondary battery remains excessively discharged during start-up of an electric-vehicle fuel cell, an external power supply is rendered operative to drive auxiliary units during fuel-cell start-up and catalytic combustion of fuel is used for heating a reformer and coolant.
Japanese Patent Application Laid-Open Publication No. 2002-219926 discloses a control system wherein a command is transmitted from a portable telephone to remotely control an air conditioning unit of a vehicle.